function initialize()
{
	document.form.expr1.value=Math.floor(Math.random()*11)
	document.form.expr2.value=Math.floor(Math.random()*11)
			
}

function validate()
{
	var expr1 = document.form.expr1.value - 0
	var expr2 = document.form.expr2.value - 0
	var result = document.form.result.value - 0	
	
	
	if((document.form.company.value=="")||(document.form.phone.value=="")||(document.form.username.value=="")||(document.form.email.value=="")) 
	{
		alert('please kindly fill all the fields')
		return false;
	}

	if(document.form.company.value.length<4)
	{
		alert('Please enter the full name of your Company')
		return false;
	}
	if(document.form.phone.value.length<5)
	{
		alert('invalid Phone Number , please enter some other number')	
		return false;
	}
	
	if(!isNumber(document.form.phone.value))
	{	
		alert('phone number must be numeric ')	
		return false; 
	}	
	
		
	if (!isValidEmail(document.form.email.value)) 
	{
        alert("Please enter a valid email address");
        return false;
	}
	
	if(result != expr1 + expr2)
	{
		alert('please enter the correct result')
		return false;	
	}
	
	
	 document.form.submit();
	 
	return true;

}

function isNumber(number)
{
	  var check_this = number;
	  var expression = /\D/;
	  if(expression.test(check_this))
		return false;
	  else
		return true;
	return true;
	  
}


function isValidEmail(email, required) 
{
    if (required==undefined)    // if not specified, assume it's required
        required=true;
 
    if (email==null) {
        if (required) {
            return false;
        }
        return true;
    }
    if (email.length==0) {  
        if (required) {
            return false;
        }
        return true;
    }
    if (! allValidChars(email)) {  // check to make sure all characters are valid
        return false;
    }
    if (email.indexOf("@") < 1) { //  must contain @, and it must not be the first character
        return false;
    } else if (email.lastIndexOf(".") <= email.indexOf("@")) {  // last dot must be after the @
        return false;
    } else if (email.indexOf("@") == email.length) {  // @ must not be the last character
        return false;
    } else if (email.indexOf("..") >=0) { // two periods in a row is not valid
	return false;
    } else if (email.indexOf(".") == email.length)   // . must not be the last character
	return false;    
    return true;
}
 
function allValidChars(email) {
  var parsed = true;
  var validchars = "abcdefghijklmnopqrstuvwxyz0123456789@.-_";
  for (var i=0; i < email.length; i++) {
    var letter = email.charAt(i).toLowerCase();
    if (validchars.indexOf(letter) != -1)
      continue;
    parsed = false;
    break;
  }
  return parsed;
}

